### Please describe the problem.

Using the SHA256E backend should preserve file extensions. This works for most of my files, but not files with a `.numbers` extension. Without the extension in the filename, Numbers (Excel of Apple) can not open the file (as described elsewhere in the forums). Copying the file from the `.git/annex/objects` and re-adding the extension allows me to open the file again, so the file is intact.

I think it might be that git annex does not recognize `.numbers` as an extension because of its length? 

### What steps will reproduce the problem?

Adding a file with `.numbers` extension (e.g. `git annex add bids.numbers`) will drop the extension in the `.git/annex/objects`

[[!format sh """
bids.numbers -> ../.git/annex/objects/Xp/xZ/SHA256E-s225502--a420fa2986ddd5e4fad39758e91bc753f5f1199a64c47c84b5bd5b9c288b66c2/SHA256E-s225502--a420fa2986ddd5e4fad39758e91bc753f5f1199a64c47c84b5bd5b9c288b66c2
"""]]

### What version of git-annex are you using? On what operating system?

[[!format sh """
git-annex version: 10.20221103
build flags: Assistant Webapp Pairing FsEvents TorrentParser MagicMime Benchmark Feeds Testsuite S3 WebDAV
dependency versions: aws-0.22.1 bloomfilter-2.0.1.0 cryptonite-0.30 DAV-1.3.4 feed-1.3.2.1 ghc-8.10.7 http-client-0.7.13.1 persistent-sqlite-2.13.1.0 torrent-10000.1.1 uuid-1.3.15 yesod-1.6.2.1
key/value backends: SHA256E SHA256 SHA512E SHA512 SHA224E SHA224 SHA384E SHA384 SHA3_256E SHA3_256 SHA3_512E SHA3_512 SHA3_224E SHA3_224 SHA3_384E SHA3_384 SKEIN256E SKEIN256 SKEIN512E SKEIN512 BLAKE2B256E BLAKE2B256 BLAKE2B512E BLAKE2B512 BLAKE2B160E BLAKE2B160 BLAKE2B224E BLAKE2B224 BLAKE2B384E BLAKE2B384 BLAKE2BP512E BLAKE2BP512 BLAKE2S256E BLAKE2S256 BLAKE2S160E BLAKE2S160 BLAKE2S224E BLAKE2S224 BLAKE2SP256E BLAKE2SP256 BLAKE2SP224E BLAKE2SP224 SHA1E SHA1 MD5E MD5 WORM URL X*
remote types: git gcrypt p2p S3 bup directory rsync web bittorrent webdav adb tahoe glacier ddar git-lfs httpalso borg hook external
operating system: darwin x86_64
supported repository versions: 8 9 10
upgrade supported from repository versions: 0 1 2 3 4 5 6 7 8 9 10
local repository version: 10
"""]]

### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)

git annex makes me so happy. As I had mentioned in a previous post some years ago, it solves problems that I have not anticipated and teaches me new concepts that I then apply across my work. Thank you so much Joey! :bow:

> [[notabug|done]] --[[Joey]]
